Nutritional and endocrine-metabolic aberrations in amenorrheic athletes.

摘要: Growing evidence suggests that menstrual disturbances in female athletes are related to the metabolic cost of high levels energy expenditure without compensatory increases dietary intake. However, linkage(s) between nutritional deficits and reproductive impairments as a result slowing LH pulsatility has not been defined. This study was directed simultaneously characterize intake, insulin sensitivity (by rapid iv glucose tolerance test), 24-h dynamics insulin/glucose, cortisol, somatotropic [GH/GH-binding protein (GHBP)/insulin-like growth factor I (IGF-I)/IGF-binding proteins (IGFBPs)], axes highly trained with (cycling athletes; CA) (amenorrheic AA) cyclicity age- body mass index-matched cycling sedentary controls (CS; n = 8/group). Although daily caloric intake did differ among three groups, (CA consumed less fat than CS. restriction 50% greater (P < 0.01) AA CA accompanied by increased carbohydrate 0.05) fiber Athletes, independent status, had reduced during feeding phase day. Hypoinsulinemia more pronounced CA, extending throughout day, increments response meals 0.05), seen CA. Levels insulin-dependent IGFBP-1 were markedly elevated 0.001) diurnal pattern AA, whereas modest elevation occurred only portion for groups inversely (r -0.63) directly cortisol 0.69) levels. A 70-80% augmentation mean GH both athletes, but distinct pulsatile features. pulse amplitude 60% no change number, displayed frequent pulses, an baseline pulses. The distorted pulses associated 35% decrease GHBP levels, IGF-I IGFBP-3 either or 2- 4-fold higher CS resulted 3-fold ratio IGF-I/IGFBP-1 which may bioactivity hypoglycemic effect IGF-I. frequency progressively attenuated unaccompanied alterations positively 0.65) 0.69), negatively -0.70) -0.75) concentrations. Stepwise regression analysis suggested negative influences hypercortisolemia predominate determining GnRH/LH activity these athletes. In sum, although neuroendocrine-metabolic adaptations exercise training evident from their counterparts, hypometabolic state, including decreased basal temperature plasma serum GHBP, IGF-I/IGFBP-1, accelerated frequency, interpulse Thus, sensitivity, circulating insulin, together concentrations comprise cascade glucoregulatory repartition fuels conservation protein. (ABSTRACT TRUNCATED)